Help With Installing the Plantronics APN-91 EHS Cable for NEC Phones NEC phones come programmed with varying settings regarding headsets. Most of the time the APN-91 cable will work without issues. On occasion the audio will work, but you don’t have the ability to answer/hangup remotely. When that occurs, we suggest the following: 1) On the Plantronics wireless headset base (CS500 series, W700 Savi series, … Continued